Introduction

Geography (from Greek: γεωγραφία, geographia, literally "earth description") is a field of science devoted to the study of the lands, features, inhabitants, and phenomena of the Earth and planets. The first person to use the word γεωγραφία was Eratosthenes (276–194 BC). Geography is an all-encompassing discipline that seeks an understanding of Earth and its human and natural complexities—not merely where objects are, but also how they have changed and come to be.

Geography is often defined in terms of two branches: human geography and physical geography. Human geography deals with the study of people and their communities, cultures, economies, and interactions with the environment by studying their relations with and across space and place. Physical geography deals with the study of processes and patterns in the natural environment like the atmosphere, hydrosphere, biosphere, and geosphere.

Geomatics is defined in the ISO/TC 211 series of standards as the "discipline concerned with the collection, distribution, storage, analysis, processing, presentation of geographic data or geographic information". Under another definition it "consists of products, services and tools involved in the collection, integration and management of geographic data".It includes geomatics engineering (and surveying engineering) and is related to geospatial science (also geospatial engineering and geospatial technology). Read more...

New York City, one of the largest urban areas in the world

Urban geography is the subdiscipline of geography that derives from a study of cities and urban processes. Urban geographers and urbanists examine various aspects of urban life and the built environment. Scholars, activists, and the public have participated in, studied, and critiqued flows of economic and natural resources, human and non-human bodies, patterns of development and infrastructure, political and institutional activities, governance, decay and renewal, and notions of socio-spatial inclusions, exclusions, and everyday life. Read more...

Development geography is a branch of geography which refers to the standard of living and its quality of life of its human inhabitants. In this context, development is a process of change that affects people's lives. It may involve an improvement in the quality of life as perceived by the people undergoing change. However, development is not always a positive process. Gunder Frank commented on the global economic forces that lead to the development of underdevelopment. This is covered in his dependency theory.

Photogrammetry is the art and science of making measurements from photographs, especially for recovering the exact positions of surface points. Photogrammetry is as old as modern photography, dating to the mid-19th century and in the simplest example, the distance between two points that lie on a plane parallel to the photographic image plane, can be determined by measuring their distance on the image, if the scale (s) of the image is known.

Spatial citizenship describes the ability of individuals and groups to interact and participate in societal spatial decision making through the reflexive production and use of geo-media (geographic media such as maps, virtual globes, GIS, and the Geoweb). Spatial citizens are lay users who are able to use geo-media to question existing perspectives on action in space (e.g. social rules, spatial planning) and to produce, communicate, and negotiate alternative spatial visions.

Geochronology is the science of determining the age of rocks, fossils, and sediments using signatures inherent in the rocks themselves. Absolute geochronology can be accomplished through radioactive isotopes, whereas relative geochronology is provided by tools such as palaeomagnetism and stable isotope ratios. By combining multiple geochronological (and biostratigraphic) indicators the precision of the recovered age can be improved.

Geochronology is different in application from biostratigraphy, which is the science of assigning sedimentary rocks to a known geological period via describing, cataloging and comparing fossil floral and faunal assemblages. Biostratigraphy does not directly provide an absolute age determination of a rock, but merely places it within an interval of time at which that fossil assemblage is known to have coexisted. Both disciplines work together hand in hand, however, to the point where they share the same system of naming rock layers and the time spans utilized to classify layers within a stratum. Read more...

Land cover surrounding Madison, WI. Fields are colored yellow and brown, water is colored blue, and urban surfaces are colored red.

Landscape ecology is the science of studying and improving relationships between ecological processes in the environment and particular ecosystems. This is done within a variety of landscape scales, development spatial patterns, and organizational levels of research and policy.

As a highly interdisciplinary field in systems science, landscape ecology integrates biophysical and analytical approaches with humanistic and holistic perspectives across the natural sciences and social sciences. Landscapes are spatially heterogeneous geographic areas characterized by diverse interacting patches or ecosystems, ranging from relatively natural terrestrial and aquatic systems such as forests, grasslands, and lakes to human-dominated environments including agricultural and urban settings. The most salient characteristics of landscape ecology are its emphasis on the relationship among pattern, process and scale, and its focus on broad-scale ecological and environmental issues. These necessitate the coupling between biophysical and socioeconomic sciences. Key research topics in landscape ecology include ecological flows in landscape mosaics, land use and land cover change, scaling, relating landscape pattern analysis with ecological processes, and landscape conservation and sustainability. Read more...

Geological mapping software displaying a screenshot of a structure map generated for an 8500ft deep gas & Oil reservoir in the Earth field, Vermilion Parish, Erath, Louisiana. The left-to-right gap, near the top of the contour map indicates a Fault line. This fault line is between the blue/green contour lines and the purple/red/yellow contour lines. The thin red circular contour line in the middle of the map indicates the top of the oil reservoir. Because gas floats above oil, the thin red contour line marks the gas/oil contact zone.

Geologic modelling,geological modelling or geomodelling is the applied science of creating computerized representations of portions of the Earth's crust based on geophysical and geological observations made on and below the Earth surface. A geomodel is the numerical equivalent of a three-dimensional geological map complemented by a description of physical quantities in the domain of interest.Geomodelling is related to the concept of Shared Earth Model; which is a multidisciplinary, interoperable and updatable knowledge base about the subsurface.

Deforestation (seen here in the Amazon) is a major driver of land change worldwide, and is often a subject of land change models.

Land change models (LCMs) describe, project, and explain changes in and the dynamics of land use and land-cover. LCMs are a means of understanding ways that humans are changing the Earth's surface in the past, present, in forecasting land change into the future.

Economic geography has been defined by the geographers as the study of human's economic activities under varying sets of conditions which is associated with production, location, distribution, consumption, exchange of resources, and spatial organization of economic activities across the world. It represents a traditional subfield of the discipline of geography. However, many economists have also approached the field in ways more typical of the discipline of economics.

Remote sensing is the acquisition of information about an object or phenomenon without making physical contact with the object and thus in contrast to on-site observation, especially the Earth. Remote sensing is used in numerous fields, including geography, land surveying and most Earth Science disciplines (for example, hydrology, ecology, meteorology, oceanography, glaciology, geology); it also has military, intelligence, commercial, economic, planning, and humanitarian applications.

In current usage, the term "remote sensing" generally refers to the use of satellite- or aircraft-based sensor technologies to detect and classify objects on Earth, including on the surface and in the atmosphere and oceans, based on propagated signals (e.g. electromagnetic radiation). It may be split into "active" remote sensing (i.e., when a signal is emitted by a satellite or aircraft and its reflection by the object is detected by the sensor) and "passive" remote sensing (i.e., when the reflection of sunlight is detected by the sensor). Read more...

Phytogeography (from Greek φυτόν, phytón = "plant" and γεωγραφία, geographía = "geography" meaning also distribution) or botanical geography is the branch of biogeography that is concerned with the geographic distribution of plantspecies and their influence on the earth's surface. Phytogeography is concerned with all aspects of plant distribution, from the controls on the distribution of individual species ranges (at both large and small scales, see species distribution) to the factors that govern the composition of entire communities and floras. Geobotany, by contrast, focuses on the geographic space's influence on plants. Read more...

Geographers drawing on this tradition see cultures and societies as developing out of their local landscapes but also shaping those landscapes. This interaction between the natural landscape and humans creates the cultural landscape. This understanding is a foundation of cultural geography but has been augmented over the past forty years with more nuanced and complex concepts of culture, drawn from a wide range of disciplines including anthropology, sociology, literary theory, and feminism. No single definition of culture dominates within cultural geography. Regardless of their particular interpretation of culture, however, geographers wholeheartedly reject theories that treat culture as if it took place "on the head of a pin". Read more...

Political geography is concerned with the study of both the spatially uneven outcomes of political processes and the ways in which political processes are themselves affected by spatial structures. Conventionally, for the purposes of analysis, political geography adopts a three-scale structure with the study of the state at the centre, the study of international relations (or geopolitics) above it, and the study of localities below it. The primary concerns of the subdiscipline can be summarized as the inter-relationships between people, state, and territory. Read more...

Geobiology is a field of scientific research that explores the interactions between the physical Earth and the biosphere. It is a relatively young field, and its borders are fluid. There is considerable overlap with the fields of ecology, evolutionary biology, microbiology, paleontology, and particularly biogeochemistry. Geobiology applies the principles and methods of biology and geology to the study of the ancient history of the co-evolution of life and Earth as well as the role of life in the modern world. Geobiologic studies tend to be focused on microorganisms, and on the role that life plays in altering the chemical and physical environment of the lithosphere, atmosphere, hydrosphere and/or cryosphere. It differs from biogeochemistry in that the focus is on processes and organisms over space and time rather than on global chemical cycles.

Geobiological research synthesizes the geologic record with modern biologic studies. It deals with process - how organisms affect the Earth and vice versa - as well as history - how the Earth and life have changed together. Much research is grounded in the search for fundamental understanding, but geobiology can also be applied, as in the case of microbes that clean up oil spills. Read more...

Regional geography is a major branch of geography. It focuses on the interaction of different cultural and natural geofactors in a specific land or landscape, while its counterpart, systematic geography, concentrates on a specific geofactor at the global level. Read more...

The history of geography includes many histories of geography which have differed over time and between different cultural and political groups. In more recent developments, geography has become a distinct academic discipline. 'Geography' derives from the Greekγεωγραφία – geographia, a literal translation of which would be "to describe or write about the Earth". The first person to use the word "geography" was Eratosthenes (276–194 BC). However, there is evidence for recognizable practices of geography, such as cartography (or map-making) prior to the use of the term geography. Read more...

Related areas of study include environmental studies and environmental engineering. Environmental studies incorporates more of the social sciences for understanding human relationships, perceptions and policies towards the environment. Environmental engineering focuses on design and technology for improving environmental quality in every aspect. Read more...

Although geophysics was only recognized as a separate discipline in the 19th century, its origins date back to ancient times. The first magnetic compasses were made from lodestones, while more modern magnetic compasses played an important role in the history of navigation. The first seismic instrument was built in 132 AD. Isaac Newton applied his theory of mechanics to the tides and the precession of the equinox; and instruments were developed to measure the Earth's shape, density and gravity field, as well as the components of the water cycle. In the 20th century, geophysical methods were developed for remote exploration of the solid Earth and the ocean, and geophysics played an essential role in the development of the theory of plate tectonics. Read more...

Stourhead in Wiltshire, England, designed by Henry Hoare (1705–1785), "the first landscape gardener, who showed in a single work, genius of the highest order"

Landscape architecture is the design of outdoor areas, landmarks, and structures to achieve environmental, social-behavioural, or aesthetic outcomes. It involves the systematic investigation of existing social, ecological, and soil conditions and processes in the landscape, and the design of interventions that will produce the desired outcome. The scope of the profession includes landscape design; site planning; stormwater management; erosion control; environmental restoration; parks and recreation planning; visual resource management; green infrastructure planning and provision; and private estate and residence landscape master planning and design; all at varying scales of design, planning and management. A practitioner in the profession of landscape architecture is called a landscape architect. Read more...

Group photo at the 12th International Geography Olympiad in Russia in August 2015.

The International Geography Olympiad (iGeo) is an annual competition for 16- to 19-year-old geography students from all over the world. Students chosen to represent their countries are some of the best, chosen from thousands of students who participate enthusiastically in their own National Geography Olympiads. iGeo tests the abilities of every participants in spatial patterns and processes. The iGeo consists of three parts: a written test, a multimedia test and a substantial fieldwork exercise requiring observation, leading to cartographic representation and geographical analysis. The programme also includes poster presentations by teams, cultural exchanges, and time for students to get to know their fellow students and explore the host city.

Table of geography, hydrography, and navigation, from a 1728 Cyclopaedia.

Hydrography is the branch of applied sciences which deals with the measurement and description of the physical features of oceans, seas, coastal areas, lakes and rivers, as well as with the prediction of their change over time, for the primary purpose of safety of navigation and in support of all other marine activities, including economic development, security and defence, scientific research, and environmental protection. Read more...

Earth science or geoscience includes all fields of natural science related to the planetEarth. This is a branch of science dealing with the physical constitution of the Earth and its atmosphere. Earth science is the study of our planet’s physical characteristics, from earthquakes to raindrops, and floods to fossils. Earth science can be considered to be a branch of planetary science, but with a much older history. Earth science encompasses four main branches of study, the lithosphere, the hydrosphere, the atmosphere, and the biosphere, each of which is further broken down into more specialized fields.

There are both reductionist and holistic approaches to earth sciences. It is also the study of Earth and its neighbors in space. Some earth scientists use their knowledge of the planet to locate and develop energy and mineral resources. Others study the impact of human activity on Earth's environment, and design methods to protect the planet. Some use their knowledge about earth processes such as volcanoes, earthquakes, and hurricanes to plan communities that will not expose people to these dangerous events. Read more...

Population geography is a division of human geography. It is the study of the ways in which spatial variations in the distribution, composition, migration, and growth of populations are related to the nature of places. Population geography involves demography in a geographical perspective. It focuses on the characteristics of population distributions that change in a spatial context. This often involves factors such as where populations are found and how the size and composition of these populations is regulated by the demographic processes of fertility, mortality, and migration. Contributions to population geography are cross-disciplinary because geographical epistemologies related to environment, place and space have been developed at various times. Related disciplines include geography, demography, sociology, and economics.

Since its inception, population geography has taken at least three distinct but related forms, the most recent of which appears increasingly integrated with human geography in general. The earliest and most enduring form of population geography emerged in the 1950s, as part of spatial science. Pioneered by Glenn Trewartha, Wilbur Zelinsky, William A. V. Clark, and others in the United States, as well as Jacqueline Beujeau-Garnier and Pierre George in France, it focused on the systematic study of the distribution of population as a whole and the spatial variation in population characteristics such as fertility and mortality.Population geography defined itself as the systematic study of: Read more...

The line appears in the running text of the Geography and not as a caption on the maps themselves. Since the inscriptions are the only surviving reference to him and these manuscripts only survive from the very late 13th century, the most that can be stated conclusively is that he lived sometime between the years AD 150 and 1300, although his classical name and his epithet—"the Alexandrian"—probably places him before that city's fall to the Caliphate in 641 and not contemporary with Maximus Planudes's reconstruction of the Ptolemaic atlas after 1295.

In the Geography, Ptolemy shows his familiarity with existing maps, complaining of the inaccuracies introduced by cartographers to Marinus of Tyre's work through his failure to provide proper accompanying data, a fault Ptolemy remedied by providing sample captions in his own books VII and VIII. In those sections, he explicitly mentions that his text was to be accompanied by maps constructed according to his principles. Heeren argued for Agathodaemon having been the cartographer responsible for these original maps; Dinse for his having been the transcriber of the original papyrusscrolls to codices; and Fischer for a strictly literal reading of the inscription, showing that differences in the early manuscripts imply Agathodaemon drafted the world map but not the regional maps. Read more...

Richard Andree (26 February 1835 – 22 February 1912) was a Germangeographer and cartographer, noted for devoting himself especially to ethnographic studies. He wrote numerous books on this subject, dealing notably with the races of his own country, while an important general work was Ethnographische Parallelen und Vergleiche (Stuttgart, 1878). Read more...

Jane Jacobs as chairperson of a Greenwich Village civic group at a 1961 press conference

During his lifetime he was primarily known for his achievements in meteorology and as a pioneer of polar research, but today he is most remembered as the originator of the theory of continental drift by hypothesizing in 1912 that the continents are slowly drifting around the Earth (German: Kontinentalverschiebung). His hypothesis was controversial and not widely accepted until the 1950s, when numerous discoveries such as palaeomagnetism provided strong support for continental drift, and thereby a substantial basis for today's model of plate tectonics. Wegener was involved in several expeditions to Greenland to study polar air circulation before the existence of the jet stream was accepted. Expedition participants made many meteorological observations and were the first to overwinter on the inland Greenland ice sheet and the first to bore ice cores on a moving Arctic glacier. Read more...

John H. Holmes is Emeritus Professor of Geography at the University of Queensland. He has remained active during his "retirement" and has continued his primary research into changing resource values in Australia’s rangelands and their implications in the allocation of property rights. More specifically, his expertise relates to:

Policy input into issues relating to property rights and appropriate policy directions, tied to pastoral leases in all Australian jurisdictions.

Interpretation of driving forces and regional outcomes affecting the ownership, use and market value of rural land in Australia in the multifunctional transition.

Interpretation of population change and future directions in rural and remote Australia.

Liú Ān (Chinese: 劉安, c. 179–122 BC) was a Han dynasty Chinese prince and an advisor to his nephew, Emperor Wu of Han (武帝). He is best known for editing the (139 BC) Huainanzi compendium of Daoist, Confucianist, Buddhist and Legalist teachings and for supposedly inventing tofu. Early texts represent Liu An in three ways: the "author-editor of a respected philosophical symposium", the "bumbling rebel who took his life to avoid arrest", and the successful Daoist adept who transformed into a xian and "rose into the air to escape prosecution for trumped-up charges of treason and flew to eternal life." Read more...

Henri Hauser (19 July 1866 – 27 May 1946) was a French historian, geographer, and economist. A pioneer in the study of the economic history of the early modern period, he also wrote on contemporary economic issues and held the first chair in economic history to be established at a French university. He was born in Oran into a middle-class Jewish family who had moved to French Algeria for health reasons but returned to France when Hauser was four years old. Hauser was educated at the Lycée Condorcet in Paris and then at the École Normale Supérieure where he came first in both the entrance and leaving examinations. He initially taught in provincial lycées before taking his doctorate in 1892 with a thesis on the 16th-century Huguenot leader, François de la Noue. Hauser went on to become a professor of ancient and medieval history at the University of Clermont-Ferrand, modern history and geography at the University of Dijon, and finally a professor of history and economic history at the Sorbonne from 1919 to 1936. His 1905 book L'impérialisme américain predicted the decline of Europe and the dominance of the United States, while his 1915 Méthodes allemandes d'expansion économique analyzed the role played by German industry in the outbreak of World War I. Hauser was awarded the Legion of Honor in 1919 and in 1945 the Académie française awarded him the Prix de l'Académie for his life's work. Read more...

He was born in Córdoba in 1126 to a family of prominent judges—his grandfather was the chief judge of the city. In 1169 he was introduced to the caliph Abu Yaqub Yusuf, who was impressed with his knowledge, became his patron and commissioned many of Averroes' commentaries. Averroes later served multiple terms as a judge in Seville and Córdoba. In 1182, he was appointed as court physician and the chief judge of Córdoba. After Abu Yusuf's death in 1184, he remained in royal favor until he fell into disgrace in 1195. He was targeted on various charges—likely for political reasons—and was exiled to nearby Lucena. He returned to royal favor shortly before his death on 11 December 1198. Read more...

Hipparchus was born in Nicaea, Bithynia (now İznik, Turkey), and probably died on the island of Rhodes. He is known to have been a working astronomer at least from 162 to 127 BC. Hipparchus is considered the greatest ancient astronomical observer and, by some, the greatest overall astronomer of antiquity. He was the first whose quantitative and accurate models for the motion of the Sun and Moon survive. For this he certainly made use of the observations and perhaps the mathematical techniques accumulated over centuries by the Babylonians and by Meton of Athens (5th century BC), Timocharis, Aristyllus, Aristarchus of Samos and Eratosthenes, among others. He developed trigonometry and constructed trigonometric tables, and he solved several problems of spherical trigonometry. With his solar and lunar theories and his trigonometry, he may have been the first to develop a reliable method to predict solar eclipses. His other reputed achievements include the discovery and measurement of Earth's precession, the compilation of the first comprehensive star catalog of the western world, and possibly the invention of the astrolabe, also of the armillary sphere, which he used during the creation of much of the star catalogue. Read more...

Michael Mortimore (born 7 September 1937, Bermuda, died 10 September 2017) was a British geographer and a prolific researcher of issues in the African drylands. He was an academic in Nigerian universities for over 25 years. He ran a British research consultancy, Drylands Research. He is best known for an anti-Malthusian account of population-environment relationships, More People, Less Erosion, and field-based studies of adaptation to drought. Read more...